A379595 Numbers k for which A376900(k) = k.

0, 385, 386, 387, 390, 392, 404, 405, 406

Offset: 1

Author

Felix Huber, Dec 26 2024

Keywords

• nonn
• fini
• full

Comments

The primitive Pythagorean triples cause A376900(n) to grow slightly overproportionally in relation to n, apart from minor fluctuations. This is why this sequence is finite and full.

Links

• Felix Huber, Right Triangles belonging to A376900(k)=k

Crossrefs

Cf. A376900.

Programs

Maple

A379595:=proc(k)
   local a,p,q,v,m;
   a:=0;
   for p from 2 to evalf(sqrt(sqrt(2)*k+1)) do
      for q from 1 to min(p-1,floor(k/(sqrt(2)*p))) do
         if gcd(p,q)=1 and is(p+q,odd) then
            v:=max(p^2-q^2,2*p*q);
            m:=min(p^2-q^2,2*p*q)/v;
            a:=a+floor(k/v*sqrt(m^2-2*m+2));
         fi
      od
   od;
   if a=k then
      return k
   fi
end proc;
seq(A379595(k),k=0..1000);